31,803 research outputs found
SLIC Based Digital Image Enlargement
Low resolution image enhancement is a classical computer vision problem.
Selecting the best method to reconstruct an image to a higher resolution with
the limited data available in the low-resolution image is quite a challenge. A
major drawback from the existing enlargement techniques is the introduction of
color bleeding while interpolating pixels over the edges that separate distinct
colors in an image. The color bleeding causes to accentuate the edges with new
colors as a result of blending multiple colors over adjacent regions. This
paper proposes a novel approach to mitigate the color bleeding by segmenting
the homogeneous color regions of the image using Simple Linear Iterative
Clustering (SLIC) and applying a higher order interpolation technique
separately on the isolated segments. The interpolation at the boundaries of
each of the isolated segments is handled by using a morphological operation.
The approach is evaluated by comparing against several frequently used image
enlargement methods such as bilinear and bicubic interpolation by means of Peak
Signal-to-Noise-Ratio (PSNR) value. The results obtained exhibit that the
proposed method outperforms the baseline methods by means of PSNR and also
mitigates the color bleeding at the edges which improves the overall
appearance.Comment: 6 page
Head and scapular posture in flutists: a pilot controlled study
Instrumental practice which requires asymmetrical postures might, in
the long term, potentiate musculoskeletal disorders and lead to pain.
This, in turn, may have a negative impact on musical performance quality.
Thus, the assessment of postural deviations among musicians is of
the outmost importance in instrumental pedagogy. This study aims to
compare the head and scapular posture of flutists with different levels of
expertise and a control group of singers. Results suggest that flutists have
a significantly more forward head posture than singers. No significant
differences were found for any other head or scapular posture measurement.
Contrary to what was hypothesized, years of instrumental practice
did not contribute to a more asymmetrical posture.head posture; scapular posture; instrumental practice; flutists
Spin-orbit mode transfer via a classical analog of quantum teleportation
We translate the quantum teleportation protocol into a sequence of coherent
operations involving three degrees of freedom of a classical laser beam. The
protocol, which we demonstrate experimentally, transfers the polarisation state
of the input beam to the transverse mode of the output beam. The role of
quantum entanglement is played by a non-separable mode describing the path and
transverse degrees of freedom. Our protocol illustrates the possibility of new
optical applications based on this intriguing classical analogue of quantum
entanglement.Comment: 5 pages, 7 figure
Gravitational Collapse of Massless Scalar Field with Negative Cosmological Constant in (2+1) Dimensions
The 2+1-dimensional geodesic circularly symmetric solutions of
Einstein-massless-scalar field equations with negative cosmological constant
are found and their local and global properties are studied. It is found that
one of them represents gravitational collapse where black holes are always
formed.Comment: no figure
Experimental study on a metal hydride based hydrogen compressor
This is the post-print version of the final paper published in Journal of Alloys and Compounds. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2008 Elsevier B.V.A three-stage metal hydride based hydrogen compressor prototype was built. It has been designed for a hydrogen production facility using a low-pressure alkaline electrolyser. The compression system should transfer heat recovered from the electrolyser into the hydride beds to allow hydrogen desorption flow. The three-stage compressor achieves a compression ratio of 20:1 atm. It performs a thermal cycling of three AB5 hydrides between 20 and 80 °C. Its flow rate, for 25 g of each hydride bed, reaches about 20 l (NTP) of hydrogen per hour. The prototype is now operational. Some improvements in the heat transfer management system are also carried out before proceeding to the interconnection with the electrolyser and to the extent that the hydrogen produced satisfies the high purity requirement of the hydrides used in the compressor.Natural Resources Canada(NRCan), Ministère des Ressources Naturelles
et de la Faune du Québec (MRNF), and Natural Sciences and Engineering Research Council of Canada
Perturbed Self-Similar Massless Scalar Field in the Spacetimes with Circular Symmetry in 2+1 Gravity
We present in this work the study of the linear perturbations of the
2+1-dimensional circularly symmetric solution, obtained in a previous work,
with kinematic self-similarity of the second kind. We have obtained an exact
solution for the perturbation equations and the possible perturbation modes. We
have shown that the background solution is a stable solution.Comment: no figure
Evaluation of de novo RNA-Seq assemblers in differential expression experiments.
The objective of this study is to evaluate methodologies applied on de novo transcriptomics studies, proposing criteria for ranking the data, in order to maximize the chance of correctly identifying a differentially expressed transcript.X-meeting 2015
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